Applications to rule evidence inadmissible at the trial of a Northern Irish man accused of possessing an explosive substance have been dismissed at the Special Criminal Court today.

Counsel for Samuel Devlin (aged 55) had applied to the court to rule inadmissible evidence about a detonating cord, found in a hotel room in Lucan, as well as samples of the accused man's DNA.

Mr Devlin, with an address at Golf Suite, Finnstown House Hotel, Lucan, Co Dublin has pleaded not guilty to the unlawful possession of the explosive substance (PETN) at the same address on May 11, 2014.

It is the prosecution's case that Mr Devlin booked into the chalet at Finnstown House Hotel using a false name and that an explosive substance was found in the chalet while he was residing there.

Previously, Bernard Condon SC, for Mr Devlin, applied to the court for the trial's evidence to be heard in voir dire.

A voir dire, or "trial within a trial", is a hearing to determine the admissibility of evidence.

Today, at the voir dire's conclusion, Mr Condon argued against the admissibility of some of the evidence.

He submitted to the court that samples of DNA taken from Mr Devlin while he was in custody were inadmissible because the garda who took the samples did not properly inform the accused man that the samples might be used in evidence against him.

Mr Condon also objected to the evidence of Detective Garda Brian Barry, who previously told the court that, after comparing rolls of detonating cord found in the Finnstown Hotel room with pieces of plastic tubing found in a bin outside the hotel, concluded the exhibits were similar.

The basis for Mr Condon's objection to this evidence was that the detonating cord has since been destroyed, the court heard.

The court has previously heard evidence from a member of the Irish armed forces, who said that, in accordance with safety regulations, the detonating cord was destroyed.

Mr Justice Paul Butler, presiding with Judge Alison Lindsay and Judge William Hamill, dismissed Mr Condon's applications, ruling that the testimony of Det Gda Barry, as well as the DNA samples, could be admitted into evidence.

The judge said that the requirements when collecting a DNA sample from an accused man were "properly complied with".

In relation to the evidence about the detonating cord, the judge stated that only part of the cord was destroyed, that samples of the cord had been retained and continued to be available for the defence.

Earlier today, the prosecution closed its case with evidence from a member of the National Surveillance Unit (NSU), who cannot be named for legal reasons.

Under cross-examination, the detective told Mr Condon that on May 9, 2014, he observed Mr Devlin leave the Finnstown House Hotel via the back gate on a bicycle.

The detective drove onto Adamstown Avenue, did a U-turn, parked and watched Mr Devlin, the court heard.

The detective said that Mr Devlin had a plastic bag.

"It would've been in his right hand. I can't say for sure if it was in his right hand or hanging from the bicycle's handlebars but it would have been on the right hand of the bicycle," he told the court.

The detective saw the bag clearly, he told Mr Condon.

The court heard that the detective went to the bin and retrieved the plastic bag.

The trial is expected to conclude tomorrow with closing speeches from the prosecution and the defence.