Convicted Air India bomb maker Inderjit Singh Reyat will serve the longest perjury sentence in Canadian history, after B.C. Court of Appeal rejected a plea to reduce the term.

The nine-year prison sentence for lying at the trial of two men accused in the terrorist plot is appropriate, the panel of three judges announced Thursday.

"The gravity of the trial at which Mr. Reyat perjured himself is without comparison," Justice Mary Saunders wrote on behalf of the panel.

Reyat hid the extent of his knowledge of the conspiracy alleged to be behind the mass murder, the judges noted.

"Mr. Reyat's testimony ... is a stain on the Canadian trial process, leaving the record in that singular case incomplete. No case before has considered false professions of lost memory in circumstances of such scale."

Reyat is the only person ever convicted in the bombings of two flights that originated in Vancouver.

Ripudaman Singh Malik and Ajaib Singh Bagri were acquitted in 2005 of murder and conspiracy charges by a B.C. Supreme Court judge.

Longest criminal trial in Canadian history

Flight 182 went down in the Irish Sea on June 23, 1985, killing all 329 people on board. A second bomb destined for Air India flight 301 went off prematurely at Narita airport in Japan, killing two baggage handlers.

After being extradited back to Canada from Britain, Reyat was convicted in 1991 of two counts of manslaughter for building the bomb that exploded in Japan.

In 2003 — as Malik and Bagri were on trial for murder —​ Reyat pleaded guilty to a third, single count of manslaughter for his role in the downing of Flight 182 and was called to testify at their trial.

Reyat's testimony offered little evidence, as he claimed again and again to have no recollection of events.

In acquitting Malik and Bagri following the longest criminal trial in Canadian history, B.C. Supreme Court judge Ian Josephson called Reyat an "unmitigated liar."

He was charged with perjury and convicted of lying 19 times at the trial.

'Little expression of remorse' for perjury

Reyat's lawyer, Ian Donaldson, told the appeal court last November that Reyat — who has spent most of his adult life in prison — was remorseful about the bombing deaths and gained nothing when he lied at the trial.

He suggested the prison term be reduced to six or seven years.

But Crown lawyer Len Doust told the judges he doubted the man's remorse, saying Reyat behaved in the witness box like a man still committed to a cause.

The Crown contended the bomb plot was hatched by Sikh separatists in Canada in retaliation for a deadly 1984 raid by Indian authorities on the Golden Temple, considered the holiest shrine in Sikhism.

Doust told the appeal court hearing that Reyat may not have planned an elaborate lie, but he did intend to obstruct the truth.

"He was completely evasive, in my submission, in regard to the whole issue of who made the bomb, and how the bomb was made," Doust told the hearing.

The appeal court agreed.

"There seems to be little expression of remorse" for the perjury, Saunders wrote.

Appeal dismissed, judge rules

Reyat argued at the appeal hearing that he lied in order not to expose himself and his family to retribution by others.

"This seems to be a continuing rejection of Mr. Reyat's obligation to testify truthfully, and greatly waters down the impact of any statement of remorse in regards to Mr. Reyat's overall participation in the plot that caused the destruction of Air India flight 182," Saunders wrote.

The decision was announced at a brief hearing Thursday morning.

"The offence was grave, and in comparison to other perjury cases, the sentence imposed was not unfit. The appeal is dismissed," Judge Edward Chiasson said on behalf of the three judges on the panel.