LOISELLE, J.

The plaintiff was convicted of a violation of General Statutes 19-480 (a) and 19-452 in selling a cannabis-type drug. Upon appeal that conviction was sustained. State v. Lombardo, 163 Conn. 241, 304 A.2d 36. Lombardo petitioned for a new trial on the ground of newly discovered evidence. The trial court rendered judgment denying the petition and from that judgment this appeal has been taken.

At the trial in which Lombardo was convicted, two undercover agents testified that they purchased four kilos of marijuana from the defendant. The defendant denied the charges, and offered in his defense an alibi. The jury rendered a verdict of guilty.

At the original trial, the state offered evidence that Ronald Minas, a detective, had met a man, whom he identified in court as the defendant, in Wickham Park in Manchester four or five times during July, 1970, and that each time they had discussed a sale of marijuana. On the evening of July 22, 1970, Minas and his associate, Officer John C. Mayoros, met with Lombardo at Wickham Park and advised him that they wished to buy as much marijuana as possible for $1000. Plans were made for delivery the next morning at the park. Minas gave his telephone number to Lombardo, so that Lombardo could call him concerning the time for the sale. At about 9 a.m., July 23, 1970, Minas received a telephone call at his home from Lombardo. Arrangements were made for the sale of four kilos of marijuana at Wickham Park at 11 a.m. that morning. Southern New England Telephone Company records showed a call from Lombardo's telephone to Minas' telephone on that day.

Minas and Mayoros, the two undercover officers, drove to Wickham Park. Shortly after 11 a.m. Lombardo drove up in a blue Ford. Dominick Lisella arrived in a white Pontiac registered to one Robert Majewski. Lisella opened the trunk of Lombardo's vehicle and a suitcase was opened which contained twenty-four kilos of a substance later identified as marijuana. Minas chose four kilos of this substance from the suitcase and Lombardo accepted $1000 from Mayoros. Minas was never more than two or three feet from Lombardo during the entire transaction.

At the original trial before the jury the defendant offered evidence concerning his claim of an alibi. This included testimony by the defendant and by a number of witnesses that on July 22, when the state's evidence put him at Wickham Park arranging for the marijuana sale, he was continuously with friends; that he attended a wake, visited someone at a hospital and returned home, but never went to Wickham Park. His alibi for the time of the sale the next day was based on his own testimony, and on the testimony of a friend who saw him at home, preparing to attend a funeral, without an operable car available, at about 11 a.m. on the 23rd, shortly before the state's evidence put him at the park selling marijuana. Another witness testified that she had telephoned Lombardo at his home and had spoken with him three or four times between 11 a.m. and 12:30 p.m. on the 23rd, and that she picked him up at his home at 12:45 to go to a funeral.

Another witness for the defense was Robert Majewski, the owner of the white Pontiac mentioned by the state's witnesses. He testified that he spent the night of the 22nd at Lombardo's home, arriving when Lombardo returned with friends from the wake. He also testified that at 10 a.m. on the 23rd he, Dominick Lisella, and Richard Putinas drove the Majewski car to Wickham Park, leaving Lombardo at home in bed. At the park, Lisella and Putinas met "Ron" and "Jack" (presumably the two undercover agents, Ronald Minas and John Mayoros) and drove to a rear parking lot together. He, Majewski, had left the car and was helping two girls wax their car and did not see what went on in the rear lot. Although he was at the park all day on the 22nd and the 23rd, he did not see Lombardo at the park either day.

At the original trial Dominick Lisella also testified for the defense. He was a boyhood friend and neighbor of Lombardo, to whom he was like a brother. He testified that he met "Ron" and "Jack" on the evening of July 22nd and discussed "business" with them, but he did not see Lombardo at the park. He spent the night with Lombardo and made a telephone call the next morning from Lombardo's telephone, but he refused to tell to whom he made the call. After the call he went to the park with Putinas and Majewski. He met "Ron" and "Jack" at the park and went with them to the back parking lot. He declined to testify further on direct examination, claiming he might incriminate himself.

According to the memorandum of decision, five witnesses testified at the hearing on the petition for a new trial. The testimony of three of those witnesses was discounted by the court as merely cumulative or repetitious of testimony given at the trial. The "new evidence" which the plaintiff claims warrants a new trial is the testimony of Putinas, who did not testify at the original trial, and Lisella, who gave some testimony at the original trial but then invoked the fifth amendment. This "new" testimony is that on the evening of July 22, Lisella made arrangements with Minas and Mayoros for the sale of marijuana, that he made a telephone call to them from Lombardo's home on the morning of the 23rd, put a suitcase of marijuana in the trunk of Majewski's car, drove to the park with Majewski and Putinas, let Majewski out and drove to the back parking lot where he opened the trunk. Putinas and Lisella "participated" in the sale. Minas and Mayoros took the marijuana and gave Lisella the money. Lombardo was not present at the sale.

At the hearing, it was explained that Putinas had told Lombardo's counsel at the original trial that he would testify that he participated in the sale, but that on advice from his attorney he changed his mind. Lombardo's counsel issued a subpoena for him, but the sheriff could not find him. Counsel for Lombardo did not ask for a continuance because he concluded that after Lisella claimed the privilege against self-incrimination there was no hope Putinas would testify.

The court denied the petition for a new trial, concluding that the testimony of Lisella and Putinas was basically cumulative of testimony given by Majewski and others at the original trial and contradictory to testimony of the undercover officers. It concluded that the case turned on the credibility of witnesses whom the jury had had an opportunity to observe, and that it did not appear that an injustice had been done or that a new trial with the additional testimony would result in a different verdict.

A petition for a new trial is addressed to the legal discretion of the trial court. State v. Grimes, 154 Conn. 314, 325, 228 A.2d 141; Smith v. State, 141 Conn. 202, 207, 104 A.2d 761. "The rules for granting a new trial on the ground of newly discovered evidence are well established. The evidence must, in fact, be newly discovered, material to the issue on a new trial, such that it could not have been discovered and produced on the former trial by the exercise of due diligence, not merely cumulative and likely to produce a different result. Turner v. Scanlon, 146 Conn. 149, 163, 148 A.2d 334." Pass v. Pass, 152 Conn. 508, 511, 208 A.2d 753; Hamlin v. State, 48 Conn. 92, 93.

It is true that in a capital case, which this is not, "[a]ll of the . . . rules [relating to new trials] are qualified . . . in the light of the principle laid down in Andersen v. State, 43 Conn. 514, 517, that `in a case where human life is at stake, justice, as well as humanity, requires us to pause and consider before we apply those rules in all their rigor.'" Taborsky v. State, 142 Conn. 619, 623, 116 A.2d 433; Hamlin v. State, supra, 94.

Whether a new trial should be granted does not turn on whether the evidence is such that the jury could extend credibility to it. A petition for a new trial is a civil action. The plaintiff has the burden of proof, by the preponderance of the evidence. "A petition will never be granted except on substantial grounds." State v. Grimes, supra, 325. The plaintiff must persuade the court that the new evidence he submits will probably, not merely possibly, result in a different verdict at a new trial, or that an injustice has been done. Pradlik v. State, 131 Conn. 682, 686, 41 A.2d 906. It is not sufficient for him to bring in new evidence from which a jury could find him not guilty — it must be evidence which persuades the judge that a jury would find him not guilty. Judge Cardozo of the New York Court of Appeals had occasion to consider this problem in a case when a new trial was sought because state witnesses had recanted their prior testimony. Concurring in affirming denial of the new trial, he rejected the view that a judge, faced with conflicting stories, should abandon the search for truth and turn it over to a jury. He said: "I think it was the duty of the trial judge to try the facts, and determine as best he could where the likelihood of the truth lay. . . . He was not at liberty to shift upon the shoulders of another jury his own responsibility." People v. Shilitano, 218 N.Y. 161, 180, 112 N.E. 733; see 58 Am.Jur.2d, New Trial, 166.

At first blush it might appear that where a person confesses to a crime and will testify to that effect, that testimony is of such weight that it, is not only material to the issue of the innocence or guilt of an accused, but would necessarily also be likely to produce a different result. In this case, however, the evidence does not rise to that level. The evidence claimed to be new is that Lisella arranged for and made the sale, that Putinas was present at the time of the sale and "participated" in it, and that Lombardo was not there. Analyzing this evidence, it does not contradict or add significantly to the evidence produced at the trial to the jury. At that trial, Majewski's testimony was that both Lisella and Putinas were at the scene of the sale. Lisella, before his refusal to continue to testify, stated that he was the one who had discussed "business" with the undercover agents the night before the sale, had made a telephone call on the next morning from Lombardo's house, had driven with Majewski and Putinas to Wickham Park, had met the undercover agents and went to the back parking lot. The undercover agents testified that at the parking lot Lisella was the one who opened the trunk of the vehicle; Lisella's participation in the sale was evidence which was produced by the state and stood uncontradicted by anyone. The only new contradictory evidence was that the money was passed to Lisella rather than to Lombardo, and that Lombardo was not there. At most, the testimony of Putinas makes him an interested observer. The totality of the new evidence boils down to being cumulative to the claimed alibi, which was the subject of extensive testimony at the jury trial.

In view of the evidence produced at the trial to the jury which made Lisella a participant, according to the state's witnesses and by inference from Majewski's and Lisella's own testimony, the claimed new evidence is not of the same substance as that which gave concern in Smith v. State, supra. Essentially, the whole story is one that the jury heard at the trial, although some facts which the jury might have inferred are filled in by the new testimony. The jury judged the credibility of the witnesses and found Lombardo guilty.

Under all the circumstances it cannot be said that the trial court abused its discretion in concluding that the evidence in all probability would not, if offered in a new trial, produce a different result, and in concluding that no injustice had been done.