Forty cars were seized last year over unpaid tolls.
In total, there were 172 criminal convictions in 2018 for persistent failure to pay fines.
Transport Infrastructure Ireland has said that while compliance with the barrier free tolling system on the M50 is at 97%, some 950 cases of unpaid fines were sent to the Dublin Sheriff last year.
According to today's examiner newspaper, forty cars were seized by the Dublin Sheriff from drivers who continually refused to pay fines and dodged tolls.
There were also 172 criminal convictions over unpaid fines- up 49% on the 2017 figure.
More than 158 million euro was paid in tolls by 2.3 million motorists.